public class ZLinkMain {
    public static void main(String[] args) {
        ZLinkImpl zLink = new ZLinkImpl();
        zLink.add("1");
        zLink.add("2");
        zLink.add("3");
        zLink.add("4");
        zLink.add("2","5");
        System.out.println(zLink.size);
    }
}
